Sampling of fish for the purpose of estimating standing crop, annual net production, and the degree of relationship between these two variables was carried out in four Oklahoma farm ponds in 1965. Fish populations were assumed to be at or near the upper asymptotic level, and fishing was almost nonexistent. Annual rate of turnover varied less from one population to another than did standing crop. Turnover rates for most species appeared high, but this may be the normal situation in older ponds whose fish populations are not being harvested. Bartlett's three-group method for Model II regression was used to obtain the prediction equation: annual net production =0.3465 + 0.6088 (standing crop). This equation showed by its positive slope that annual net production increased as standing crop increased. The coefficient of determination, r2=0.92, indicated a strong relationship between standing crop and the annual net production of fishes.
